Multiprocessor systems employing miniprocessors or microprocessors, have become a powerful means for carrying out distributed processing functions. These distributed processors have a need for rapid access time mass storage capable of storing millions of words of operational and diagnostic programs, permanent data, and intermediate results. Distributed processing creates the demand for higher system performance for mass storage. The prior art has employed memory and buffering arrangements for digital computers using a conventional architecture for a cache memory by a single processor communicating with a bulk storage device. There has been no adequate solution in the prior art, however, for sharing a bulk storage device with a plurality of distributed processing elements.